Income Taxes - Reconciliation of Total Amounts of Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Unrecognized tax benefits, balance at the beginning	$ 11,865us-gaap_UnrecognizedTaxBenefits	$ 11,196us-gaap_UnrecognizedTaxBenefits	$ 10,297us-gaap_UnrecognizedTaxBenefits
Additions based on tax positions related to the current year	4,472	1,690	1,342
Additions for tax positions of prior years	47		41
Lapse of statute of limitations	(1,040)	(1,067)	(942)
Translation adjustment	(375)	46	458
Unrecognized tax benefits, balance at the ending	$ 14,969us-gaap_UnrecognizedTaxBenefits	$ 11,865us-gaap_UnrecognizedTaxBenefits	$ 11,196us-gaap_UnrecognizedTaxBenefits

Unrecognized Tax Benefits Increases Decrease Resulting From Foreign Currency Translation

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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